This invention relates generally to a dual filter system and apparatus and more specifically to a replaceable water filter carrying a water purification composition dispersibly secured therein to enable the water filter to simultaneously and in situ purify water as water flows through the water filter while minimizing disruption to the normal flow of water through the filter system.
In water treatment systems it is known that bacteria killing materials such as metal ions are effective in killing bacteria. One commonly used metal ion is the silver ion and another commonly used bacteria killing and material is the zinc ion. Other types of ions are used as algaecides. The difficulty in use of metal ions is to maintain the ion concentration within proper ranges since too low metal ion concentration results in ineffective killing of bacteria and to high metal ion concentrations can be harmful. Another difficulty is to be able to controllable release the materials to provide for water purification over an extended period of time.
It has been demonstrated that a single bacteria killing material that releases silver ions can be effectively used to kill bacteria in water systems such as spas, hot tubs and swimming pools over an extended period of time. In some cases multiple bacteria killing materials that releases both ions of silver and zinc are used to kill bacteria over an extended period of time.
In one embodiment of a bacteria killing material I use an adhesive that is securable to both a metal ion generating material and to a particle carrier that is placed in a container within the water supply. Water is allowed to flow through the container as the bacteria killing material controllable release metal ions to kill bacteria in the water. While the use of bacteria killing materials that release metal ions is known, the present invention is directed to the structure and mechanism for holding the bacteria killing materials so as not to interfere with the release of the bacteria killing materials such as metal ions without disrupting the normal flow of water through the system.
In most recirculation systems such as for swimming pools, spas and hot tubs a filter is included that removes unwanted waste particles from the water. In one embodiment, which is shown in U.S. Pat. No. 4,780,197 a container is placed in the core of the filter. The container is filled with a bacteria killing material such as chlorine or bromine. In this type of arrangement one can provide for removal of waste particles as well as killing of bacteria in the same part of the system. While this type of system brings the bacteria killing and water purification into the filter housing it does not provide for in situ killing of bacteria and removal of debris. However, more importantly, devices placed in the core of the filter create obstructions to normal flow though the fluid filter. The first obstruction to normal flow is the container itself which hold the bactericide and the second obstruction to normal flow is the materials that are placed in the container. In the present invention the obstruction to normal flow of water through the filter system is substantially eliminated as the bacteria killing material is either secured directly to the filter medium or to a portion of the filter where the flow area is generally the largest thereby allowing one to maintain the normal flow patterns of the filter mechanism.
In the present invention, a water treatement composition, for example, a water purification material, such as a bacteria killing material is secured to a replaceable filter that normally removes debris from the water. With the present invention the replaceable filter performs a dual in situ function in that the filter simultaneously removes debris and kills bacteria. Consequently, when the filter is replaced due to accumulation of debris thereon the bacteria killing material is replaced in the same operation thus minimizing the consumer maintenance in maintaining a water system in proper condition. Thus the present invention becomes consumer friendly as the need for maintenance of the system can be reduced.
In one embodiment of the dual filter apparatus of the present invention, a bacteria killing material is affixed directly to fibers that are formed into a filter medium with the fibers formed into a network for screening removal of debris from the water. As water is directed through the filter medium formed from the fibers containing the bacteria killing material the filter medium traps debris thereon, while the bacteria killing material kills bacteria thereon. In this embodiment the dual filter apparatus simultaneously accomplishes the in situ task of both filtering debris from the water and killing bacteria as the water passes through the filter. Other embodiments and refinement of the invention are described herein. The preferred embodiment is described in relation to a water purification material comprising a bacteria killing material and other water purification materials such as algaecides, clarifiers or pH adjusters can be used with the present invention.
Briefly, the present invention comprises an in situ water purification system comprising a replaceable dual filter having a porous medium for removing debris and a bacteria killing material thereon for killing bacteria while minimizing obstruction to normal flow through the system as well as a process of making a water purification device by dispersibly securing a bacteria killing material to a filter medium for removing debris.